Laser-Directed Self-Organization and Reaction Control in Complex Systems

Pulsed lasers proved to be advantageous tools for the stimulation of pattern formation in complex systems. Their capability to support thermodynamic, kinetic and spatial control facilitates the direction of self-organization processes into selective channels. The short lifetime of laser-stimulated p...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
1. Verfasser: Reinhardt, Hendrik Martin
Beteiligte: Hampp, Norbert (Prof. Dr) (BetreuerIn (Doktorarbeit))
Format: Dissertation
Sprache:Englisch
Veröffentlicht: Philipps-Universität Marburg 2013
Chemie
Schlagworte:
Online Zugang:PDF-Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Pulsed lasers proved to be advantageous tools for the stimulation of pattern formation in complex systems. Their capability to support thermodynamic, kinetic and spatial control facilitates the direction of self-organization processes into selective channels. The short lifetime of laser-stimulated processes was identified to be the key aspect that enables for the synthesis of functional materials starting from complex systems. When self-organization is abruptly stopped after a few nanoseconds, this creates materials present in a non-equilibrium state, which are known to exhibit special properties. A prominent example is the distinctively different behavior of gold nanoparticles compared to bulk gold. Repeated laser stimulation was demonstrated to be a powerful method that enables selective adjustments of material properties emergent in the course of self-organized pattern formation in complex systems. This includes a broad spectrum of optical, electrical, magnetic and catalytic properties, which are not found in the starting materials prior to laser modification. The capability of lasers to trigger self-organization processes with spatial control was identified to be an interesting feature because it bears the potential to create materials with advanced functionality. In particular, the utilization of a phenomenon called laser-induced periodic surface structures (LIPSS) proved to be very efficient. LIPSS transformed the surface of stainless steel into hierarchical structures thus equipping this everyday material with a multifunctional surface. Considering the simplicity of the generation process this demonstrates the viability of nature’s low-effort-high-outcome-principle of order formation in complex systems. In addition to that, the application breath of laser-stimulated pattern formation was successfully expanded to temperature sensitive materials by including photochemistry into the concept. The large variety of reaction types accessible via photochemistry opens an even wider field of potential applications. In conclusion, it can be stated that the concept of nature to trigger selective reorganizations and pattern formation in complex systems can be imitated in its principles. The introduced concept of laser-directed self-organization and reaction control in complex systems prospects a large application potential. Presented insights into laser-stimulated reaction pathways and pattern formations processes provide a valuable basis for future studies in this field. Overall, the major challenge that must be met on the way to beneficial applications is the need for purposeful design of materials, which requires a thorough understanding of the fundamental principles behind self-organization.
DOI:https://doi.org/10.17192/z2013.0490